David Sweat Spent 6 Months Planning Escape From New York Prison, Investigators Say

— -- David Sweat spent six months planning his escape from a New York prison, roaming around inside the prison’s walls and underground tunnels scouting an escape route, he told investigators following his capture.

Investigators told ABC News that Sweat divulged that he would crawl out of a hole he cut in his cell at Clinton Correctional Facility in Dannemora at 11:30 p.m. each night, making sure he was back by the 5:30 a.m. count.

Sweat shimmied down a pipe, eventually busting a hole through a brick wall, then spotted a hot steam pipe that led to the outside. According to authorities, Sweat waited until spring, when the heating system was shut off, then spent weeks cutting the pipe with a hacksaw.

Details about Sweat's account of the escape to investigators were first reported by the New York Times.

Sweat and fellow inmate Richard Matt escaped from the facility on June 6, spending three weeks on the run.

The two went separate ways following their escape, after Matt began drinking and talking about shooting at law enforcement. Matt was also talking about possibly taking a hostage, Sweat told investigators.

Matt was shot and killed June 26. Sweat was wounded and captured two days later, and he is now being held at Five Points Correctional Facility in Romulus, New York.

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